Atypical rhabdoid/teratoid tumor (ATT/RHT) is a rare malignant neoplasm which appears in early childhood. The present paper describes clinical and pathological features of ATT/RHT which occurred simultaneously in 2 sisters diagnosed at a 15 day interval. Both children were treated by surgical resection, subtotal in the first case and total in the second. Postoperatively, chemotherapy followed by radiotherapy, 50.4 Gy on the posterior fossa, were administered. Despite this therapy, both sisters died at 14 months and 26 months respectively. The tumors express vimentin and EMA; cells contained intracytoplasmic inclusions. No karyotypic anomaly was detected. This is the first description of familial ATT/RHT.